The common clinical causes of stomach pain and nausea are intestinal infection, ulcerative colitis, Crohn’s disease, etc. This disease is usually associated with poor dietary habits, such as eating rotten food or drinking raw food. 1. Intestinal infection: this disease is usually associated with the existence of poor dietary habits of the sick people, such as eating rotten food or drinking raw water, etc., which may cause intestinal infection by bacteria, viruses and other pathogenic microorganisms, clinical manifestations of abdominal pain, diarrhea, vomiting and other symptoms. 2. Ulcerative colitis: this disease refers to a chronic non-specific intestinal inflammatory disease, which is related to the environment, genetics, autoimmunity, intestinal microcirculation and other factors, the clinical manifestations of intermittent diarrhea, acute and severe abdominal pain, mucus, pus and blood stools, vomiting and so on. 3. Crohn’s disease: this disease refers to a chronic inflammatory granulomatous disease of the digestive tract of unknown etiology, which is usually associated with the environment, infection and intestinal flora, genetics and other factors, clinical manifestations include diarrhea, weight loss, abdominal pain, etc., and the course of the disease is relatively slow, with the remission period and the active period occurring alternately. It is recommended that people with the disease should supplement amino acids, vitamins, glucose and other nutrients as appropriate, and at the same time, they should go to the hospital for the usual examination to clarify the causes of abdominal pain, nausea and other symptoms, so as to carry out targeted treatment.